This is an interesting study that could get 20kg into Pluto orbit. It uses gridded ion engines coupled to multiple Radioisotope Thermal Generators. PDF: http:/

This is an interesting study that could get 20kg into Pluto orbit. It uses gridded ion engines coupled to multiple Radioisotope Thermal Generators. PDF: http://www.esa.int/gsp/ACT/doc/PRO/ACT-RPR-PRO-ISTS2004-Pluto.pdf http://www.esa.int/gsp/ACT/doc/PRO/ACT-RPR-PRO-ISTS2004-Plut...